Solar Fest San Antonio provides valuable information to the public about renewable energy technologies, the impact of sustainable living and green building techniques. Lion's Field, Saturday, Oct. 6, 2012.

Solar Fest San Antonio provides valuable information to the public about renewable energy technologies, the impact of sustainable living and green building techniques. Lion's Field, Saturday, Oct. 6, 2012.

George Witta explains the workings of the "Eloo," the Enviro Loo toilet to homebuilder Mark Fahnert (elft) as Solar Fest takes place in Maverick Park on May 7, 2011. The toilet system evaporates waste from the toilet.

George Witta explains the workings of the "Eloo," the Enviro Loo toilet to homebuilder Mark Fahnert (elft) as Solar Fest takes place in Maverick Park on May 7, 2011. The toilet system evaporates waste from

Marko Mendez (left) shows off his solar evacuated thermal tube array to prospective buyer Abel Videl as Solar Fest takes place in Maverick Park on May 7, 2011. The system is designed for use in water heating in domestic applications and also for air conditioning and heating applications.

Marko Mendez (left) shows off his solar evacuated thermal tube array to prospective buyer Abel Videl as Solar Fest takes place in Maverick Park on May 7, 2011. The system is designed for use in water heating

SolarPump inventor Beth Ferguson (right) and Brad Spies of South by Southwest Marketing, both from Austin, adjust solar panels just as the sun emerges from the clouds during Solar Fest at Maverick Park on May 1, 2010. Ferguson created the SolarPump as a solar charging station for people to re-charge their electronic devices or electric scooters and bikes. Ferguson came up with the idea as part of her thesis for her Masters in Fine Art degree from the University of Texas.

SolarPump inventor Beth Ferguson (right) and Brad Spies of South by Southwest Marketing, both from Austin, adjust solar panels just as the sun emerges from the clouds during Solar Fest at Maverick Park on May

ONTility solar trainer and consultant Eddie Haynes (left) of Houston is reflected while discussing the use of a device called a Solar Pathfinder at Solar Fest at Maverick Park on May 1, 2010. Haynes said the device helps people find the optimal position for their solar panels to get the most efficiency. ONTility was one of many vendors on hand to showcase the latest in solar energy technology.

ONTility solar trainer and consultant Eddie Haynes (left) of Houston is reflected while discussing the use of a device called a Solar Pathfinder at Solar Fest at Maverick Park on May 1, 2010. Haynes said the